(i) Headlights of a car- Convex mirror (ii) Side/rear-view mirror of a vehicle – Convex mirror (iii) Solar furnace – Concave mirror (iv) Dentist’s mirror – Concave mirror

Statement (1) is correct. Doppler Effect is the change in frequency of a wave for an observer moving relative to its source. The radio signal received from a moving vehicle will help in tracking an artificial satellite. Statement (2) is incorrect. Radio waves are also called TV waves.

(I) Solution 1 is incorrect. The visible spectrum runs from about 400 nm to about 700 nm. (II) Solution 2 is also incorrect. Narinder Singh Kapany is known as the 'father of fibre optics'.

Statement 1 is incorrect. The three distinct parts of a shadow created by a light source are: (i) Umbra - The innermost and darkest part of a shadow, where the light source is completely blocked by the body. (Total eclipse) (ii) Penumbra - The region in which only a portion of the light source is observed by the body. (Partial eclipse) (iii) Antumbra - The region from which the body appears entirely contained within the disc of the light source. Statement 2 is correct. Sundogs may appear as a coloured patch of light to the left or right of the sun, and at the same distance above the horizon as the sun, and in ice halos.

A periscope is an instrument, which is used for observation from a concealed position. The principle of periscope simply involves the reflection and refraction of light.

A rainbow is the path in which light refracts into the droplet, internally reflects, and then refracts out of the droplet, which results in the dispersion of light into a spectrum of colours.

Statement 1 is correct. The minimum distance from the eye at which an object appears to be distinct is called least distance of distinct vision or near point, which is 25 cm from the eye. If the object is held closer to the eye than the distance the image formed will be blurred and fuzz. Statement 2 is also correct. A mirror coating reflects the sun rays, which does not get hot in sunlight and prevents the scattering of rays in the lens bulk. The reflecting optical coating is present for the protection against the glare of sunlight.

Statement 1 is wrong. A red object appears black when viewed through blue glass because red object reflects only red colour and absorbs all the other colours, so it looks black. Statement 2 is also incorrect. The ratio of the speed of light in a vacuum to the speed of light in a material is known as refractive index.

All of these reflect light and their surface produce brightness when light falls on them.

Statement (1) is correct. Flint glass is used in the preparation of lenses and prisms. Statement (2) is incorrect. The waves received by our television sets are micro waves (radio waves).

(1)  Shape of a rain drop - (b) Surface tension (2) Lustre of a diamond - (d) Total internal reflection

Statement (1) is correct. An air bubble in water behaves as a concave lens, which diverges the sun rays falling on it.  Statement (2) is incorrect. The duration of day appears to be increased by 4 min. due to atmospheric refraction. (2 min. in the morning and 2 min. in the evening)

(1) Micro waves (radio waves) - (d) Broadcasting (TV/Radio) (2) Infra red rays - (a) Micro wave oven (3) X - rays - (b) CT scan (4) UV rays - (c) Water Purifier

Statement 1 is incorrect. A mirage is caused by the total internal reflection of light at layers of air of different densities. Statement (2) is correct. Water bubbles shine because of total internal reflection. The speed of light is faster inside an air bubble than in water. Thus, the light gets reflected away from the bubble around outside, looking like a mirror.

Statement 1 is correct. Holography is a technique, which enables three-dimensional images to be made. It involves the use of a laser, interference, diffraction, and light intensity. Statement 2 is also correct. Oil or soap film appears coloured due to interference. Thin-film interference is the phenomenon that occurs when incident light waves reflected by the upper and lower boundaries of a thin film and interfere with one another to form a new wave.